Safety device for water-cooled electron tubes



April 1938- 's. ODARTCHENKO 2,115,559

SAFETY DEVICE FOR WATER-COOLED ELECTRON TUBES Filed May 14, 1955 INVENTOR SERGE ODARTCHENKO BY N ATTORNEY UNITED STATES PATENT OFFICE SAFETY DEVICE FOR WATER-COOLED ELECTRON TUBES Serge Odartchenko, Paris, France, assignor to Compagnie Generale de Telegraphic Sans Fil, a corporation France Application May 14, 1935, Serial No. 21,412 In France June 26, 1934 3 Claims. (Cl. 250-27) This invention relates to a new and novel safeway of example, shows a preferred embodiment ty device for electron tubes cooled by water circuof the basic idea of the invention and. is intended lation, and is concerned with a safety device deto give a clearer understanding of the invention.

signed to protect electron tubes of large power Referring to the drawing, A denotes the water- 5 which are normally cooled by a current of water, cooling vat of the anode or plate. This vat is from overheating. traversed by a water current indicated by the A water-cooled power-tube consists generally arrows. The water supplied from general water of a. glass bulb or tube welded onto a metal cylinmains or from a special pump flows first through der which constitutes the anode or plate. The the insulation coil E, then across the said vat A,

latter is immersed in a metallic vat in which 0001- flows in contact with the elements responsive to ing water is circulated. The plate and the vat temperature variations, such as a bimetallic strip being operated at a high potential (say, 10,000 T, for instance, controlling an electric contact D, volts above ground), coils consisting of insulaand leaves through the second insulation coil F. tion material are placed between the said vat In order to preclude all chances of direct elecand the water conduit which feeds the same, the trio connection between the contact D and the 15 insulation consisting of caoutchouc, steatite, and safety or check-up means to be actuated thereby, the like. according to the embodiment here illustrated, the

To check up on the rise of the temperature of scheme includes an ordinary illuminating or the plate, and in order to act upon the safety deglow-lamp B fed on radio-frequency energy and vices such as electric bells, circuit breakers, etc., a photoelectric cell C. The very proximity of the there is usually connected in the water-circulacontact D and the insulating circuits makes it tion pipe or conduit a means responsive to varia very easy to collect by virtue of induction in an tions in temperature, such as a contact-type therinductance S disposed in the neighborhood of the mometer, a bimetal leaf or spring, or the like. contact D a sufficient volume of radio-frequency However, in order to avoid the said safety circuits energy to cause lighting of the bulb or lamp B. 25 and means being subjected to the action of the The circuit of this lamp includes, therefore, only high voltage of the plate or to avoid the necessity the inductance S and the contact D, and this of the same being insulated against such a high circuit may be easily insulated from ground. Its potential, general practice of the past has been electrostatic potential moreover depends upon to mount the means sensitive to temperature the connection I which unites a point of the in- 30 fluctuations beyond the insulating coils, that is ductance S with the vat A, the two terminals of to say, sensibly at ground potential. the contact D being, themselves, insulated from This arrangement, however, involves the inconthe vat. venience that, as a result of thermal radiations The operation of the arrangement here diswhich take place along the coil (and this radiaclosed is then as follows: with the coil S being 35 tion is not negligible and is a function of the placed inside a radio-frequency field, it becomes ambient temperature) the indications available the seat of an induced electromotive force sumat the end of the coil do not give a direct or true ciently great to raise the lamp B to a state of picture of the state of heating of the anode. In incandescence. Hence, the latter will be lit when 40 other words, the operation of the safety devices the contact D is closed as a result of an undue rise 40 will or may be vitiated. of temperature. The light flux of the lamp B In order to obviate the said difficulty, accordcoming to strike the photoelectric cell C sets up ing to the present invention, the control or checkacross the terminals of the same a certain potenup device (consisting in practice, e. g. of a contial which, in turn, causes the arising of a ourtact actuated by a bimetallic strip or spring) is rent in the winding of a first, fairly sensitive, re- 45 disposed in the Water current conduit at the very lay RI. The latter will occasion closure of the outlet in the anode vat; however, at the same contact a which energizes the coil of another time all direct electric connection between the relay R2 fed from the line Z. The relay R2 besaid means and the apparatus controlled thereby comes closed in turn and acts upon the contacts (alarm bell and supply source therefor, coil of b, c, d. The contact b upon opening causes trip- 50 circuit-breaker, etc.) is avoided. ping of the circuit breaker D which interrupts the An assembly of the said kind may be carried feeding of the tube L to be safeguarded. The into practice by the aid of a photoelectric cell contact 0 closes at the same time a signal or and an ordinary glow-lamp fed by virtue of raalarm system, say, an electric bell. The contact dio-frequency induction. The attached figure, by d, finally, keeps the coil of the relay R2 ener- 55 gized after extinction of the lamp 3 until pressure is brought to act upon the button M in order to release the same, thereby resetting the safety apparatus to an operative condition.

Having thus described my invention, what I claim is:

1. Safety device insuring protection against undue rises of temperature in transmitter tubes cooled by water circulation, comprising an inductive circuit, a safety circuit breaking means, said means comprising a photoelectric cell interposed between an electric light bulb fed with radio-frequency energy by induction from said inductive circuit in order to preclude all chances of direct electric connection from the safety devices fed on low-potential current and the means responsive to the fluctuations of temperature which itself is maintained at the voltage of the anode.

2. A safety device insuring protection against an undue rise of temperature comprising an electron tube having a metallic anode, means for supplying said anode with a high potential, means for liquid cooling said anode, means controlled by the liquid temperature and controlling a contact, said contact being closed when the temperature rises above a predetermined limit, said last means being electrically connected with a high potential supply, a light source supplied by .a circuit comprising an energy source and said contact, said light source being inductively coupled with a high frequency field generated by the oscillating circuit associated with said power tube.

3. A protective device for a vacuum tube having anode water cooling means, said device comprising a lei-metallic circuit breaking means, said circuit breaking means disposed within the anode water cooled outlet of said tube, an inductive circuit connected to the anode of said tube, an electric lamp connected in series with said inductive circuit and said circuit breaking means, a photo electric cell located so as to be actuated by the light of said electric lamp, a relay circuit connected to said photo electric cell whereby the energy supply circuit for said tube is broken when a predetermined rise of temperature is reached in the anode of said tube.

SERGE ODARTCHENKO. 

